In the previous method of preparing a shell for fitting to a roll core, the inside diameter surface of the shell is ground to a finish of 30 to 40 micro-inches, honed and shrink fitted onto the core. During operation of the roll casting machine, a small amount of slippage takes place between the shell and core, which results in galling with metal pick-up on one or both members. The consequences of slippage and galling are severe damage to core surfaces, which must be rebuilt during shell changes, and reduction of shell service life due to loss of shape and increased heat checking.